(YYRHSLOC): New macro, taken from glr.c.

[bison.git] / data / yacc.c

diff --git a/data/yacc.c b/data/yacc.c
index 575d2624e6386b2436caeb851cfa6665ae1d47a0..40b1320b236804329f291242b2a2c5ef5c34d6d9 100644 (file)
--- a/data/yacc.c
+++ b/data/yacc.c
@@ -506,14 +506,29 @@ while (0)
 #define YYERRCODE      256
 
 
-/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].  */
+/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
+   If N is 0, then set CURRENT to the empty location which ends
+   the previous symbol: RHS[0] (always defined).  */
 
+#define YYRHSLOC(Rhs, K) ((Rhs)[K])
 #ifndef YYLLOC_DEFAULT
-# define YYLLOC_DEFAULT(Current, Rhs, N)               \
-   ((Current).first_line   = (Rhs)[1].first_line,      \
-    (Current).first_column = (Rhs)[1].first_column,    \
-    (Current).last_line    = (Rhs)[N].last_line,       \
-    (Current).last_column  = (Rhs)[N].last_column)
+# define YYLLOC_DEFAULT(Current, Rhs, N)                               \
+    do                                                                 \
+      if (N)                                                           \
+       {                                                               \
+         (Current).first_line   = YYRHSLOC(Rhs, 1).first_line;         \
+         (Current).first_column = YYRHSLOC(Rhs, 1).first_column;       \
+         (Current).last_line    = YYRHSLOC(Rhs, N).last_line;          \
+         (Current).last_column  = YYRHSLOC(Rhs, N).last_column;        \
+       }                                                               \
+      else                                                             \
+       {                                                               \
+         (Current).first_line   = (Current).last_line   =              \
+           YYRHSLOC(Rhs, 0).last_line;                                 \
+         (Current).first_column = (Current).last_column =              \
+           YYRHSLOC(Rhs, 0).last_column;                               \
+       }                                                               \
+    while (0)
 #endif
 
 
@@ -1021,10 +1036,7 @@ yyreduce:
 
 ]b4_location_if(
 [[  /* Default location. */
-  if (yylen)
-    YYLLOC_DEFAULT (yyloc, yylsp - yylen, yylen);
-  else
-    yyloc = yylsp[0];]])[
+  YYLLOC_DEFAULT (yyloc, yylsp - yylen, yylen);]])[
   YY_REDUCE_PRINT (yyn);
   switch (yyn)
     ]{